Generation of multiply folded optical paths

Abstract

This new technique for stacking multiply folded optical paths in an extended region of a laser resonator within a gaseous medium. The path segments are connected together by a set of mirrors located along the resonator perimeter. Moreover, this invention involves a system of stacking unit tiles, each minim containing a multiply folded path, into larger domains. A multiplicity of mirrors is located in the laser resonator around the perimeter of stacked minims. A longer optical path is achieved without a corresponding increase in the number of folding elements, by stacking the minims together and thereby extending the length of the folding elements. The resulting domains fully cover the plane with a grid of evenly spaced and intersecting optical paths. The laser resonator can be used in either a laser oscillator or amplifier, and in either pulsed or continuous wave mode. In one embodiment of this invention, a waveguide gas laser system has ceramic blocks located within the laser resonator, and each block has a multiply folded waveguide channel formed therein. The larger multiply folded optical path is formed by stacking the ceramic blocks together and aligning the waveguide channels. The reflecting mirrors of the laser resonator may be integrally attached to the ceramic block, enhancing the durability of the laser resonator and reducing its size.

We claim: 
     
       1. A laser resonator, which comprises: an active medium within the resonator capable of supporting laser action;   a plurality of solid blocks disposed within the laser resonator, each block having a smaller, multiply folded waveguide channel formed therein; and   a multiplicity of mirrors disposed within the resonator, the mirrors being located around the perimeter of the solid blocks, the mirrors being arranged to produce a larger, multiply folded optical path along the waveguide channels.   
     
     
       2. The laser resonator of claim 1, wherein the active medium is a gas, a solid, or a liquid. 
     
     
       3. The laser resonator of claim 1, wherein the waveguide channels are evenly spaced across the blocks. 
     
     
       4. The laser resonator of claim 1, wherein the waveguide channels intersect each other. 
     
     
       5. The laser resonator of claim 1, wherein the waveguide channels are substantially located within the same plane. 
     
     
       6. The laser resonator of claim 1, wherein the mirrors are coated to front reflect optical radiation. 
     
     
       7. A process for forming a laser resonator with a multiply folded optical path, which comprises: providing an active medium within the resonator capable of supporting laser action;   providing a plurality of solid blocks, each of the blocks having more than one smaller, multiply folded waveguide channel formed therein;   arranging multiplicity of mirrors around the perimeter of the resonator; and   stacking the blocks together such that the mirrors are located around the stacked blocks, and aligning the waveguide channels to form a larger, multiply folded optical path.   
     
     
       8. The process of claim 7, wherein the waveguide channels are evenly spaced across the solid blocks. 
     
     
       9. The process of claim 7, wherein the waveguide channels intersect each other. 
     
     
       10. The process of claim 7, wherein the waveguide channels are substantially located within the same plane. 
     
     
       11. The process of claim 7, wherein the mirrors are coated to front reflect optical radiation. 
     
     
       12. A laser resonator, which comprises: an active medium within the laser resonator capable of supporting laser action;   a plurality of minims disposed within the laser resonator, the minims being stacked and aligned with respect to each other; and   a multiplicity of mirrors located around the perimeter of the minims within the laser resonator, each of the mirrors being coated to front reflect optical radiation, the mirrors being aligned with respect to each other and with respect to the minims to produce a multiply folded optical path within the minims.   
     
     
       13. The laser resonator of claim 12, wherein the active medium is a solid, a liquid, or a gas. 
     
     
       14. The laser resonator of claim 12, wherein the minims each have a substantially rectangular shape. 
     
     
       15. The laser resonator of claim 14, wherein the length of the folded optical path (L) is essentially equal to:   L=2ij(a.sup.2 +b.sup.2).sup.1/2     where the rectangular minim has an "a" dimension along an axis, and a "b" dimension along another axis, "i" is the number of minims along the a-axis; and "j" is the number of minims along the b-axis.   
     
     
       16. The laser resonator of claim 12, wherein the minims each have a substantially triangular shape. 
     
     
       17. A process for forming a multiply folded optical path within a laser resonator, which comprises: providing an active medium capable of supporting laser action within the resonator;   positioning a multiplicity of mirrors around the perimeter of the minims, each mirror being coated to front reflect optical radiation; and   stacking and aligning a plurality of minims together to form a multiply folded optical path within the minims.   
     
     
       18. The laser resonator of claim 17, wherein the minims each have a substantially rectangular shape. 
     
     
       19. The laser resonator of claim 18, wherein the length of the folded optical path (L) is essentially equal to:   L=2ij(a.sup.2 +b.sup.2).sup.1/2     where the rectangular minim has an "a" dimension along an axis, and a "b" dimension along another axis, "i" is the number of minims along the a-axis; and "j" is the number of minims along the b-axis.   
     
     
       20. The laser resonator of claim 17, wherein the minims each have a substantially triangular shape.